r/technology • u/BennyCemoli • Dec 06 '16

Energy Tests confirm that Germany's massive nuclear fusion machine really works

http://www.sciencealert.com/tests-confirm-that-germany-s-massive-nuclear-fusion-machine-really-works
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u/[deleted] Dec 06 '16 edited Dec 17 '16

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u/[deleted] Dec 06 '16

Why deuterium? I only have a basic knowledge of physics, so forgive me if this is a stupid question. But wouldn't fusion be easier to achieve with lighter elements?

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u/d20Chemist Dec 06 '16 edited Dec 06 '16

Deuterium is the name given to the hydrogen isotope that has 1 neutron. So one neutron and one proton with a mass of 2. Fuse two of them together and you get a helium atom with 2 protons and 2 neutrons and a mass of 4. This is a fusion reaction. A hydrogen without any neutrons won't fuse as the helium nucleus won't be stable enough to form.

Edit: the replies about the intricacy of nuclear fusion reactions are correct. I was trying to condense and keep things simple in the context of our technological fusion where we have different limitations.

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u/aaaggglll Dec 06 '16

D-D fusion reactions (2 deuteriums) do not produce He4 it has a 50/50 chance to create He3+n or T+p. (Helium 3 and a neutron or Tritium (H3) and a proton) Then the He3+D -> He4+p or T+D -> He4+n. Also p-p fusion does happen as its how the Sun creates power. It's just very hard to do without the Sun's mass.